Experts added that any move by Opec - whose members are Iran, Iraq, Kuwait, Saudi Arabia, Venezuela, Qatar, Indonesia, Libya, United Arab Emirates, Algeria and Nigeria - is likely to be little more than a symbolic gesture.

"It's just a small step ... I don't think it's going to be enough to bring the oil price down," said Rupert Krietemeyer, spokesman for EU Energy Commissioner Andris Piebalgs.

Opec has said that while it will make extra output available, it will not be changing its official production level of 28 million barrels per day.

Should the market need any extra crude, Opec said it is willing to offer as much as 2 million more barrels a day from 1 October for three months.

"The ceiling will be maintained the same and we will offer the market what Opec can produce," said Venezuelan Energy Minister Rafael Ramirez.

While not at record levels, oil prices are remaining stubbornly high.

US light sweet crude traded at $67.30 a barrel in New York on Monday, while Brent crude closed at $64.20 in London.